title: Imaging features of desmoid-type fibromatosis in the teres major muscle.
abstract: Desmoid-type fibromatosis is a locally aggressive fibroblastic neoplasm with a tendency for local recurrence, despite adequate surgical resection. Its clinical presentation, biological behavior, and natural history can vary considerably. We present a unique case of desmoid-type fibromatosis arising in the left teres major muscle of a 62-year-old female. Physical examination showed a 7-cm, elastic-hard, immobile, tender mass. Magnetic resonance imaging (MRI) revealed a partially ill-defined mass, with intermediate signal intensity on T1-weighted sequences and heterogenous high signal intensity on T2-weighted sequences. Contrast-enhanced fat-suppressed T1-weighted sequences demonstrated intense and homogenous enhancement throughout the mass. Integrated positron-emission tomographic (PET)/computed tomographic (CT) images showed moderate focal ¹⁸F-fluorodeoxyglucose uptake corresponding to the clinically palpable and MRI-described soft tissue mass, with a maximal standardized uptake value of 4.85. The possibility of a malignant lesion was raised. Following an open biopsy, wide resection of the tumor was performed. Histological examination confirmed the diagnosis of desmoid-type fibromatosis. Finally, we discuss the imaging features of this peculiar neoplasm on MRI and PET/CT.
authors.affiliation: Department of Orthopaedic Surgery, Faculty of Medicine, Fukuoka University, 7-45-1 Nanakuma, Jonan-ku, Fukuoka 814-0180, Japan. jnishio@cis.fukuoka-u.ac.jp
authors.forename: Jun
authors.initials: J
authors.lastname: Nishio
authors.forename: Mikiko
authors.initials: M
authors.lastname: Aoki
authors.forename: Kazuki
authors.initials: K
authors.lastname: Nabeshima
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Iwasaki
authors.forename: Masatoshi
authors.initials: M
authors.lastname: Naito
mesh_terms: D001706:Biopsy; D005260:Female; D018222:Desmoid Tumors / Q000175:diagnosis*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000473:pathology*; D049268:Positron-Emission Tomography; D014057:Tomography, X-Ray Computed
keywords: Desmoid; fibromatosis; magnetic resonance imaging; positron-emission tomography; teres major muscle